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Rm = Diatance from the

Rm = Diatance from the source x' to the observation point m. (on the 8Cafferer) cp"= Angle at x' between R, and the strip.(positiw when taken anüdodmise from strip) This can be generalized to any scatterer made of strips as building blocks. The only differenœ is that the integration would be on the whole perimeter of the scatteter and the x and y components of the scatterd field are replaced by the parallel and pepndicular (to the strip) wmponent. For every strip (single building block) the proper axis rotation will have to be done depending on the angle of the stip relative to aie actual coordinate axis. The EFlE for this case is: -. EL=-EL, (2. t 9) where the component of the scattard and incident fidd taken is tangential to ihe scatterer at point m. Again equation 2.1 9 can be solved by the mmnt mahod. 2.4.2 The Moment Mefhod The current density J: in equation 2.17 can be represented by [12J[.13J: J XI # (finite series (2.20) Substiing this in equation 2.17 gives: This mes the general hm:

where VM = &(&) (known excitation function) In = constant coefficients set. C g, represent basis functions. Equation 2.20 represenb a numerical solution of the €FIE (equation 2.17). Sinœ for a given observation point at p, , it leads to one equation with N unknowns, the proœss cm be repeated for N difirent obsenration points m=1 to m=N.The Cnal outcome will be N linear equations each with N unknomis. This is better represented in matrix form: The M elemgnts are known, the [Z] ektnents can be computed and the [Il vector can be determined. This will allows us to approdmate Jz(p9) using equation 2.20 and henœ permit the computation of the radiation integral to determine the scatterd field anywttere. In words, equation 2.2 1 mam that for each observation point, the total field consists of the sum of the di- E' and scattered Es components. To find the scatterd component. the contribution of al1 segmenta of the scatterer, which include the one where the observation is made, must be added. The contribution of the local segment (Men the obsenration is made) is calleâ the self temi or diagonal term (tn). This is usually the hardest term to compute due to singulariües existent when p. = p'. Other non diagonal t em are usually easiw to compute and con be